The application is based on application Nos. 2000-26462 and 2000-26463 filed in Japan, the contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a processing device and a processing method for processing a material with ultraviolet light or light having a shorter wavelength than the ultraviolet light. In particular, the invention relates to a processing device and a processing method for effecting fine processing to produce a three-dimensional part by irradiating a material with ultraviolet light or light of a shorter wavelength than the ultraviolet light and thereby removing the material, or changing physical or chemical properties of the material.
2. Description of the Related Art
(1) First Disadvantage
It has been demanded to provide a method of processing works or materials with high accuracy to produce finely processed parts such as components of micro-machines. Photolithography and others, which are used for manufacturing semiconductor integrated circuits, have been known as some kinds of fine processing method. The fine processing technique used for manufacturing the semiconductor integrated circuits is primarily a technique for arranging parts by layering a thin film on a two-dimensional plane. The technique can arrange a layer of only up to several micrometers in thickness. Therefore, this technique cannot be used for manufacturing a part having a three-dimensional structure, which requires processing on the order of tens to hundreds of micrometers in depth.
An LIGA method using X-rays by synchrotron radiation has been known as a fine processing method, which allows processing on the order of tens to hundreds of micrometers in depth. The LIGA method was developed in Germany, and xe2x80x9cLIGAxe2x80x9d is an abbreviation for German xe2x80x9cLithographie (lithography), xe2x80x9cGalvanoformung (electro-forming)xe2x80x9d and xe2x80x9cAbformung (forming)xe2x80x9d. The LIGA method is a technology utilizing a high rectilinear property and a high energy of X-rays.
In the LIGA method, resist made of polymethyl methacrylate, which will be referred to as xe2x80x9cPMMAxe2x80x9d hereinafter, is applied to a surface of a substrate to form a layer of hundreds of micrometers in thickness, and is irradiated with X-rays to cut of molecular chains of the resist. Then, development is performed to remove the resist from exposed portions. Using the remaining resist as a die, electro-casting is performed to form a structure of metal. Molding of plastics or the like can be performed using this metal structure as a die. Thereby, accurately and finely processed parts can be manufactured in large volume.
According to the LIGA method, a process of exposing a material uses a mask-having a transparent portion transparent to X-rays for restricting a region of the resist irradiated with X-rays. Since X-rays have a high rectilinear property, the region on the resist irradiated with X-rays has the same configuration as the transparent portion. Accordingly, the mask having the transparent portion of the same configuration as the processing configuration (i.e., configuration to be produced by the processing) is used.
As described above, the LIGA method can produce the three-dimensional structure, which has a uniform section perpendicular to the incident direction of X-rays as well as a thickness of hundreds of micrometers.
However, the conventional LIGA method uses the mask having the transparent portion of the same configuration as the intended process configuration. Therefore, it is impossible to produce a three-dimensional structure, of which section perpendicular to the incident direction of X-rays varies depending on the depth In view of this, such a manner may be envisaged that an X-ray mask having a transparent portion of a smaller configuration than the process configuration is employed, and is moved relatively to the resist so that the resist may be exposed to the X-rays in accordance with an exposure amount distribution corresponding to the process configuration.
However, the configuration of the transparent portion of X-ray mask does not match with the configuration of the section perpendicular to the incident direction of X-rays, and further a processing amount of the resist (i.e., an amount by which the resist is processed) in the depth direction varies depending on the position. Therefore, it is difficult to determine the pattern of movement of the X-ray mask so that the exposure amount distribution may correspond to the intended three-dimensional processing configuration. Accordingly, it is difficult to produce the three-dimensional structure, of which section perpendicular to the incident direction of X-ray varies in configuration depending on the depth.
(2) Second Disadvantage
In the prior art, nozzle bores, which are provided in an ink-jet record head for ejecting ink, are formed by press work, electro-casting, laser processing or the like. According to the press work, a nozzle plate is pressed and deformed by dies for forming the nozzle bores. This usually causes large errors during processing in the configurations of nozzle bores, and thus causes large variations in configuration. The electro-casting method is performed with a die formed of a resist pattern prepared by photolithography so that a nozzle plate having nozzles is directly prepared. In this electro-casting method, the processible sectional form of the nozzle bore is restricted, and the error in resist pattern directly affects the configuration of the nozzle plate. According to the laser processing method, the processible sectional form of the nozzle bore is restricted to only the vertical form, Further, an error occurs in the peripheries of nozzle bores during processing, resulting in variations in configurations of the nozzle bores.
According to the conventional manufacturing method, it is difficult to achieve both kinds of processing described above, i.e., the processing for producing a three-dimensional configuration, which has a processed depth varying depending on the position, and is employed, e.g., in the nozzle bore for ejecting ink in the inkjet record head, and the processing in which variations in configuration between the processed portions are suppressed.
If an error is present in configuration of the nozzle bore, and/or variations are present in configuration between the nozzle bores, the respective nozzles have different ink ejection characteristics. The ink ejection characteristics relate to a volume of ejected ink and an ejection speed. If variations are present in ink ejection characteristics between the nozzles, inconsistencies in density occur in printed portions. Particularly, in an ink-jet record head provided with a row of many nozzles, the ink-jet record head is scanned on a record medium in a direction perpendicular to the row of nozzles for printing so that inconsistencies in density between the nozzles result in stripes along the scanning paths. The stripe noises are conspicuous in many cases, and therefore remarkably lower image quantities. For printing beautiful images with less noises, it is very important to keep uniformity in ink ejection characteristics between the nozzles.
Methods such as photolithography used for producing a semiconductor integrated circuit are also know as the fine processing methods, which can perform extremely accurate and fine processing of parts such as an ink-jet record head provided with nozzle bores to be processed, In this fine processing technique used for manufacturing the semiconductor integrated circuit, parts are arranged primarily by layering a thin layer on a two-dimensional plane. This technique can arrange the layer of only several micrometers in thickness. Thus, this technique cannot be used for manufacturing parts having three-dimensional structures, which must have sizes in depth direction on the order from tens to hundreds of micrometers.
The foregoing LIGA method is known as a fine processing method, which allows processing on the order from tens to hundreds of micrometers in the depth direction.
In the LIGA method, however, it is difficult to change the processing amount in the height direction during the one processing operation. This is because the exposure distribution of the material to be processed must be changed for changing the processing amount in the height direction. For this change, it is necessary to change a transmittance of the transparent opening of the mask. However, there is no technique that can produce such masks with a high accuracy. Accordingly, the exposure is performed multiple times with a combination of plurality of masks, or exposure and etching are repeated multiple times. However, the method in which the exposure is performed several times suffers from such a problem that the material to be processed and the mask must be positioned accurately every time the exposure is to be performed, and an error in position causes a large error in the processed configuration.
A mask, which is used in the LIGA method, is prepared, e.g., by the photolithography and electro-casting. The transparent portions of the mask thus prepared may have a configuration different from the designed configuration due to error in manufacturing in some cases. For example, if the transparent portion has a circular form, irregularities may be present in the circle of the periphery of the transparent portion. Further, the side surface of the transparent portion may not be parallel to the direction of X-rays, resulting in fine irregularities. These errors in the mask impede accurate processing.
The invention has been developed for overcoming the above disadvantages, and an object of the invention is to provide a processing device and a processing method, which allow easy processing of a material into an intended three-dimensional configuration.
Another object of the invention is to provide a processing device and a processing method, which allow processing of a material into an intended three-dimensional configuration having different processed depths while suppressing an influence exerted on a processed configuration by an error in configuration of a transparent portion.
Still another object of the invention is to provide a processing device and a processing method, which allow easy processing of a material into a configuration having portions of different processed amounts.
According to an aspect of the invention for achieving the above objects, the invention provides a processing device of processing a material by irradiating the material with ultraviolet light or light of a shorter wavelength than the ultraviolet light to remove the material, or to change physical or chemical properties of the material, including a light source for emitting the ultraviolet light or the light of the shorter wavelength than the ultraviolet light, a mask having a transparent portion of a predetermined configuration for passing the light emitted from the light source, an input portions for entering a processing configuration formed of a position on a plane of said material and a processing amount, a memory for storing a relationship between the exposure amount of the material and the processing amount, a converter for converting the processing configuration entered via the input portion into an effective exposure amount distribution formed of the position on the material plane and the exposure amount in accordance with the relationship between the exposure amount and the processing amount stored in the memory, a calculator for calculating a movement pattern for moving on the material plane an irradiation region for irradiation of the material with the light passed through the transparent portion based on the effective exposure amount distribution and the configuration of the transparent portion such that the exposure amount distribution of the material forms the effective exposure amount distribution, and a moving mechanism for moving the mask and the material relatively to each other in accordance with the calculated movement pattern.
According to the above aspect of the invention, the processing configuration which is entered through the input portion is converted into the effective exposure amount distribution formed of the position on the material plane and the exposure amount in accordance with the relationship between the exposure amount and the processing amount stored in the memory. Thereby, the effective exposure amount distribution, an intensity distribution of the light emitted to the irradiation region and the movement pattern become linear. Based on the effective exposure amount distribution and the configuration of the transparent portion, the movement pattern for moving the irradiation region on the material plane is calculated such that the exposure amount distribution of the material forms the effective exposure amount distribution. The irradiated portion and the material are moved relatively in accordance with the calculated movement pattern. Accordingly, the material is exposed in accordance with the effective exposure amount distribution. Thereby, it is possible to provide the processing device, which can easily process the material into an intended three-dimensional form.
According to another aspect, the invention provides a processing method of processing a material by irradiating the material with ultraviolet light or light of a shorter wavelength than the ultraviolet light to remove the material, or to change physical or chemical properties of the material, including the steps of emitting the ultraviolet light or the light of the shorter wavelength than the ultraviolet light to an irradiation region of a predetermined configuration, entering a processing configuration formed of a position on a plane of said material and a processing amount, converting the entered processing configuration into an effective exposure amount distribution formed of the position on the material plane and the exposure amount in accordance with a relationship between the exposure amount of the material and said processing amount, calculating a movement pattern for moving on the material plane the irradiation region based on the effective exposure amount distribution and the configuration of the irradiation region such that the exposure amount distribution of the material forms the effective exposure amount distribution, and moving the irradiation region and the material relatively to each other in accordance with the calculated movement pattern.
According to the above aspect of the invention, the entered processing configuration is converted into the effective exposure amount distribution formed of the position on the material plane and the exposure amount in accordance with the relationship between the exposure amount and the processing amount. Based on the effective exposure amount distribution and the configuration of the irradiation region, the movement pattern for moving the irradiation region on the material plane is calculated such that the exposure amount distribution of the material forms the effective exposure amount distribution. The irradiation region and the material are moved relatively in accordance with the calculated movement pattern. Accordingly, the material is exposed in accordance with the effective exposure amount distribution. Thereby, it is possible to provide the processing method, which allows easy processing of the material into an intended three-dimensional form.
According to still another aspect, the invention provides a processing device of processing a material by irradiating the material with ultraviolet light or light of a shorter wavelength than the ultraviolet light to remove the material, or to change physical or chemical properties of the material, including a light source for emitting the ultraviolet light or the light of the shorter wavelength than the ultraviolet light, a mask having a transparent portion of a predetermined configuration for passing the light emitted from the light source, a moving mechanism for moving the mask and the material relatively to each other in accordance with a movement pattern determined based on a processing configuration of the material, and an oscillating mechanism for oscillating the mask and the material relatively to each other for oscillating a region for irradiation of the material with the light passed through the transparent portion, wherein a speed of the oscillation by the oscillating mechanism is higher than a speed of movement by the moving mechanism.
According to the above aspect of the invention, the mask and the material are relatively oscillated for oscillating the region where the material is irradiated with the light passed through the transparent portion. Thereby, this region for irradiation of the material with the light passed through the transparent portion moves within a range of an amplitude of the oscillation. Accordingly, the configuration of the exposed region does not match with the configuration of the transparent portion, and matches with a configuration obtained by blurring the configuration of the transparent portion.
Since the mask and the material are moved relatively in accordance with the movement pattern determined on the basis of the processing configuration of the material, the material is exposed in accordance with the exposure distribution corresponding to the processing configuration. Therefore, the material can be processed into the three-dimensional configuration having different depths.
Since the oscillation speed of the oscillating mechanism is higher than the moving speed of the moving mechanism, the configuration of the exposed region is blued within the range of the amplitude, by which the configuration of the transparent portion oscillates. As a result, it is possible to provide the processing device, which can process the material into an intended three-dimensional configuration having different depths, and can suppress an influence exerted by the configuration of the transparent portion on the processing configuration.
According to yet another aspect, the invention provides a processing device of processing a material by irradiating the material with ultraviolet light or light of a shorter wavelength than the ultraviolet light to remove the material, or to change physical or chemical properties of the material, including a light source for emitting the ultraviolet light or the light of the shorter wavelength than the ultraviolet light, a mask having a plurality of transparent portions for passing the light emitted from the light source, and an oscillating mechanism for oscillating the mask and the material relatively to each other for oscillating a plurality of regions for irradiation of the material with the light passed through said plurality of transparent portions, wherein the plurality of transparent portions include the transparent portion occupying a unit area at a rate different from those of the other transparent portions.
According to this invention, the mask has the plurality of transparent portions for passing the light emitted from the light source, and the plurality of transparent portions include the transparent portion occupying a unit area at a rate different from those of the other transparent portions. The transparent portions, which include the transparent portion occupying a unit area at a rate different from those of the other transparent portions, pass the light to provide different exposure amounts, and therefore, can cause provide different processing amounts of the material, respectively. Consequently, it is possible to provide the processing device, which can produce the configuration having portions of different processed amounts by performing the exposure only one time.
The oscillation may include a sinusoidal wave, a rectangular wave and a triangular wave, and may also include two kinds of oscillations of different oscillation directions.
According to further another aspect, the invention provides a processing method of processing a material by irradiating the material with ultraviolet light or light of a shorter wavelength than the ultraviolet light to remove the material, or to change physical or chemical properties of the material, including the steps of emitting the ultraviolet light or the light of the shorter wavelength than the ultraviolet light to an irradiation region of a predetermined configuration, moving the irradiation region and the material relatively to each other in accordance with a movement pattern determined based on the processing configuration of the material, and oscillating the irradiation region and the material relatively to each other for oscillating the irradiation region on a plane of the material, wherein a speed of the oscillation in the oscillating step is higher than a speed of movement in the moving step.
According to the above aspect of the invention, the material can be processed into an intended three-dimensional configuration having different processing depths. Also, it is possible to provide the processing method, which can perform the processing while suppressing an influence exerted by the configuration of the irradiation region on the processing configuration.
According to a further aspect, the invention provides a processing method of processing a material by irradiating the material with ultraviolet light or light of a shorter wavelength than the ultraviolet light to remove the material, or to change physical or chemical properties of the material, including the steps of emitting the ultraviolet light or the light of the shorter wavelength than the ultraviolet light to a plurality of irradiation regions, and oscillating the plurality of irradiation regions and the material relatively to each other for oscillating the plurality of irradiation regions on a plane of the material, wherein the plurality of irradiation regions include the irradiation region occupying a unit area at a rate different from those of the other irradiation regions.
According to the above aspect of the invention, the irradiation regions, which occupy the unit areas at different rates, respectively, cause different exposure amounts in the regions where the irradiation regions move on the material plane, respectively, and therefore, can provide different processing amounts of the material, respectively. Consequently, it is possible to provide the processing method, which can produce the configuration having portions of different processed amounts by performing the exposure only one time.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.